Chris, that's beyond the scope of a mapping tool. For one thing, it would depend on each runner's pace (how far you run/walk at what speed). So, someone like me (short and slow) would have different markers (like you're asking about) than someone tall and fast.
A fitness app that incorporates mapping/gps might have allow you to mark "splits" that you would be able to check and add to a map after you're done.
Sorry Chris, I don't understand what you are trying to achieve. You can add label and symbols to the map at the interval points if that helps.
My brother is in a group doing walk/run routes - walk 1 min, run 1.5 min intervals. How do I plot a route that incorporates that with the distance completed tracker that follows the route?